Hi Thomas, Do you mean the GUIDs returned by DirectSoundEnumerate? They are actually generated within dsound.dll using this rule: <BD6DD71A-3DEB-11D1-B171-00C04FC200xx>, where xx is the order in which the devices are enumerated by SysAudio.sys. If changing the preferred audio device changes the order in which SysAudio enumerated the devices, it will change this GUID; I don't know of any way to avoid that. Dugan Porter - DirectX Audio Dev Lead - Microsoft This posting is provided "as is" with no warranties, and confers no rights -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Tom Eckert Sent: Tuesday, September 07, 2004 7:16 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] DirectX Enumeration GUIDs We've had a bug report that the GUIDs reported with DirectX enumeration for our devices change after the user changes the prefered audio device but that others in the system remain constant. Does anyone know what triggers the regeneration of the reported GUIDs for some devices? Is there some change we could make to keep the GUIDs reported for our devices constant? Thanks, Tom Thomas Eckert AudioScience Inc ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/